While the legal battle is by no means over, I think it’s not wise to talk about “preserving traditional marriage” as we often do. Because there’s hardly anything left to preserve or defend. Our culture gave up any coherent understanding of marriage years ago—which is why, instead of defending marriage, we need to rebuild it from the ground up.

Long before same-sex “marriage,” our culture abandoned the understanding of marriage as the God-ordained institution whose purpose is producing the next generation. In its place was substituted a certificate awarded for extra strong feelings of attraction.

We're All Guilty of Redefining Marriage

Under this new definition, why shouldn’t you have the right to marry someone of the same sex? What now makes or breaks a marriage—gay or straight—is the intensity of attraction. Marriage has, in many ways, become a government registry of sexual friendships.

Now this might seem like a recent definition foisted on society by the LGBT movement, but the seeds of traditional marriage’s demise in the popular imagination were sown before homosexual rights ever entered the picture. And in at least one case, they were sown by a conservative hero.

In 1970, then California Governor Ronald Reagan signed into law the prototype for no-fault divorce. Other states followed suit at an alarming rate.

Under no-fault divorce, spouses no longer had to prove infidelity or abuse to secure a divorce. Many don’t realize it, but this was marriage’s Roe v. Wade moment. And in the political blink of an eye, Americans rejected—by law—the traditional view of marriage.

In its place, Americans embraced what Princeton’s Robert George and the Heritage Foundation’s Ryan Anderson call the “revisionist view” of marriage—the idea that feelings, not marriage’s purpose and design, are the only reason to stay married for life.

Remember the widespread Christian backlash against no-fault divorce? No? That’s because there wasn’t a backlash—at least not one on the scale we’ve seen against gay “marriage.”

Our willingness to yawn at the definition shift that fractured marriage 40 years ago—but only take up arms when homosexuals wanted recognition—has not gone unnoticed. And LGBT apologists have used the Christian blind spot for divorce to great effect.

If we want to be taken seriously when we warn that same-sex “marriage” will dissolve the foundations of society, we need to take more seriously the redefinitions that got us here in the first place.

But we’re not done yet. There’s more repenting to do—including over the way we’ve treated our gay and lesbian neighbors.

Evangelicals in particular have spent decades repeating the mantra, “Hate the sin, love the sinner.” Well, we nailed the “hating sin,” part, but as Sean McDowell and I observe in our book, most of us never got around to “loving the sinner.” And, remember, biblical love is active—not passive.

That’s why, as the Anglican Book of Common Prayer leads us, we need to ask God’s forgiveness, both for the things we’ve done, and for those things we’ve left undone.